This paper proposes a new fuzzy logic approach to perform analysis and detection intrusion in 802.11 wireless networks. The algorithm consists on five steps: First, construct our networks and generating much case of daily traffic and intrusion. In same time, catch different values of system and networks parameters and associate with them a potential degree of severity alarm. Second, generate fuzzy rules from numerical data using Mendel Wang method. Third, implement new rule base on each computer and start system. Adjust it for catching parameter cyclically and compute severity alarm. If it detects intrusion, then send massage for every network node. Four, in case of no responding system or error, start learning mechanism by injection of numerical values and generating fuzzy rules.